Alert archive / Wyoming / Blizzard Warnings in 2021

Blizzard Warning 4, NWS Cheyenne, WY

December 10, 20214 counties in Wyoming

NWS Cheyenne, WY issued this blizzard warning at Dec 10, 2021, 2:48 PM MST for 4 counties in Wyoming. It took effect at Dec 10, 2021, 8:00 PM MST. It was in force for 30 hr. 4 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Dec 10, 2021, 2:48 PM MST (21:48 UTC)
In effect from
Dec 10, 2021, 8:00 PM MST
Expired
Dec 12, 2021, 2:27 AM MST
In force
30 hr
Issued by
NWS Cheyenne, WY

Counties Albany County, WY, Carbon County, WY, Laramie County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 88 km from the middle of the area, began a volume at 21:49 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Dec 10, 11:34 PM MSTBLIZZARD1 Nnw Arlington, WYWYDOT SENSOR AT ARLINGTON RECORDED FREQUENT WIND GUSTS > 35 MPH WITH VISIBILITIES UNDER 1/4 MILE BETWEEN 0816 PM AND 0100 AM. PEAK WIND GUST 71 MPH WITH 0.07 MILE VISIBILITY. 3-HOUR CRITERIA MET AT 11:34 PM.
Dec 11, 2:50 AM MSTBLIZZARD7 Ese Arlington, WYWYDOT SENSOR AT COOPER COVE RECORDED FREQUENT WIND GUSTS > 35 MPH WITH VISIBILITIES UNDER 1/4 MILE BETWEEN 1150 PM AND 350 AM. PEAK WIND GUST 75 MPH WITH 0.18 MILE VISIBILITY. 3-HOUR CRITERIA MET AT 2:50 AM.
Dec 11, 8:10 AM MSTBLIZZARDBordeaux, WYWYDOT SENSOR AT BORDEAUX RECORDED FREQUENT WIND GUSTS 60 TO 80 MPH WITH VISIBILITY NEAR 1/4 MILE BETWEEN 0500 AM AND 0800 AM. PEAK WIND GUST 95 MPH AT 0722 AM. I-25 IS ALSO CLOSED BETWEEN CHEYENNE AND WHEATLAND DUE TO WINTER CONDITIONS.
Dec 11, 11:00 AM MSTBLIZZARD1 Ene Rawlins, WYWYDOT REPORTS VIA STATE/COUNTY TROOPERS OF WHITEOUT CONDITIONS OVER THE PAST 3 HOURS. WIND GUSTS OF 35-50MPH HAVE BEEN RECORDED AT THE RWL ASOS BETWEEN 1500Z-1800Z.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 9.8 hours before the alert went out and 278 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Riverton, WY at 12:00Z on 2021-12-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 12:00Z on 2021-12-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -70 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
788 m above ground
0-6 km bulk shear
78 kt
0-1 km storm-relative helicity
-70 m²/s²
0-3 km storm-relative helicity
-37 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

194 
WWUS45 KCYS 102148
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
248 PM MST Fri Dec 10 2021

WYZ106-111200-
/O.CAN.KCYS.WS.W.0018.000000T0000Z-211211T0000Z/
/O.NEW.KCYS.BZ.W.0004.211211T0600Z-211211T1800Z/
Central Laramie Range and Southwest Platte County-
Including the city of Bordeaux
248 PM MST Fri Dec 10 2021

...BLIZZARD WARNING IN EFFECT FROM 11 PM THIS EVENING TO 11 AM
MST SATURDAY...
...WINTER STORM WARNING IS CANCELLED...

* WHAT...Blizzard conditions expected. Winds gusting as high as 
  75 mph.

* WHERE...Between Wheatland and Chugwater including Bordeaux.

* WHEN...From 11 PM this evening to 11 AM MST Saturday.

* IMPACTS...Widespread blowing snow could significantly reduce
  visibility and create whiteout conditions. The hazardous
  conditions could have large impacts on the morning commute. The
  cold wind chills as low as 15 below zero could cause frostbite 
  on exposed skin in as little as 30 minutes.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

NEZ002-003-095-096-WYZ101-102-107-108-116-102300-
/O.CAN.KCYS.WS.W.0018.000000T0000Z-211211T0000Z/
Dawes County-Box Butte County-Northern Sioux County-
Southern Sioux County-Converse County Lower Elevations-
Niobrara County-East Platte County-Goshen County-
South Laramie Range-
Including the cities of Chadron, Chadron St Park, Alliance, 
Hemingford, Harrison, Agate, Douglas, Glenrock, Bill, Deer Creek,
Lusk, Redbird, Wheatland, Guernsey, Torrington, Buford, 
Pumpkin Vine, and Vedauwoo
248 PM MST Fri Dec 10 2021

...WINTER STORM WARNING IS CANCELLED...

Periods of snow showers can be expected through early this
evening. However, little if any additional snowfall accumulation
is expected. Gusty winds will continue to cause drifting snow 
tonight. 

$$

NEZ019>021-WYZ117>119-102300-
/O.CAN.KCYS.WW.Y.0040.000000T0000Z-211211T0000Z/
Scotts Bluff County-Banner County-Morrill County-
South Laramie Range Foothills-Central Laramie County-
East Laramie County-
Including the cities of Scottsbluff, Gering, Harrisburg, Angora, 
Bridgeport, Bayard, Redington, Whitaker, Federal, Horse Creek, 
Cheyenne, and Pine Bluffs
248 PM MST Fri Dec 10 2021

...WINTER WEATHER ADVISORY IS CANCELLED...

A few snow showers are still possible through sunset. However,
little if any additional snowfall accumulation is expected. Gusty
winds will cause some blowing and drifting of snow during the
remainder of the afternoon into the evening.  

$$

WYZ110-111200-
/O.NEW.KCYS.BZ.W.0004.211211T0300Z-211212T0000Z/
North Snowy Range Foothills-
Including the cities of Arlington and Elk Mountain
248 PM MST Fri Dec 10 2021

...BLIZZARD WARNING IN EFFECT FROM 8 PM THIS EVENING TO 5 PM MST
SATURDAY...

* WHAT...Blizzard conditions expected. Winds gusting as high as 
  65 mph.

* WHERE...Between Arlington and Elk Mountain

* WHEN...From 8 PM this evening to 5 PM MST Saturday.

* IMPACTS...Widespread blowing snow will cause significant
  reduction in visibility and whiteout conditions. The cold wind 
  chills as low as 20 below zero could cause frostbite on exposed 
  skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ109-111200-
/O.NEW.KCYS.BZ.W.0004.211211T0600Z-211212T0000Z/
Central Carbon County-
Including the city of Rawlins
248 PM MST Fri Dec 10 2021

...BLIZZARD WARNING IN EFFECT FROM 11 PM THIS EVENING TO 5 PM MST
SATURDAY...

* WHAT...Blizzard conditions expected. Winds gusting as high as 
  60 mph.

* WHERE...Rawlins, Sinclair and Hannah

* WHEN...From 11 PM this evening to 5 PM MST Saturday.

* IMPACTS...Widespread blowing snow will cause significant
  reduction in visibility and whiteout conditions. The cold wind 
  chills as low as 20 below zero could cause frostbite on exposed 
  skin in as little as 30 minutes.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
5 follow-up statements
952 
WWUS45 KCYS 111252
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
552 AM MST Sat Dec 11 2021

WYZ110-120000-
/O.CON.KCYS.BZ.W.0004.000000T0000Z-211212T0000Z/
North Snowy Range Foothills-
Including the cities of Arlington and Elk Mountain
552 AM MST Sat Dec 11 2021

...BLIZZARD WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Blizzard conditions likely. Winds gusting as high as 85
  MPH. 

* WHERE...Interstate 80 near Arlington and Elk Mountain. 

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Widespread blowing snow will cause significant 
  reduction in visibility and whiteout conditions. The cold wind 
  chills as low as 20 below zero could cause frostbite on 
  exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ109-120000-
/O.CON.KCYS.BZ.W.0004.000000T0000Z-211212T0000Z/
Central Carbon County-
Including the city of Rawlins
552 AM MST Sat Dec 11 2021

...BLIZZARD WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Blizzard conditions possible. Winds gusting as high as 
  60 mph.

* WHERE...Central Carbon County especially east of Rawlins. 

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Widespread blowing snow will cause significant 
  reduction in visibility and whiteout conditions. The cold wind 
  chills as low as 20 below zero could cause frostbite on 
  exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ106-111800-
/O.CON.KCYS.BZ.W.0004.000000T0000Z-211211T1800Z/
Central Laramie Range and Southwest Platte County-
Including the city of Bordeaux
552 AM MST Sat Dec 11 2021

...BLIZZARD WARNING REMAINS IN EFFECT UNTIL 11 AM MST THIS
MORNING...

* WHAT...Blizzard conditions expected. Winds gusting as high as 85
  MPH.

* WHERE...Bordeaux along Interstate 25 between Chugwater and
  Wheatland.

* WHEN...Until 11 AM MST this morning.

* IMPACTS...Widespread blowing snow could significantly reduce 
  visibility and create whiteout conditions. The hazardous 
  conditions could have large impacts on the morning commute. 
  The cold wind chills as low as 15 below zero could cause 
  frostbite on exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

CLH
988 
WWUS45 KCYS 111747
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
1047 AM MST Sat Dec 11 2021

WYZ106-120000-
/O.EXT.KCYS.BZ.W.0004.000000T0000Z-211212T0000Z/
Central Laramie Range and Southwest Platte County-
Including the city of Bordeaux
1047 AM MST Sat Dec 11 2021

...BLIZZARD WARNING NOW IN EFFECT UNTIL 5 PM MST THIS AFTERNOON...

* WHAT...Blizzard conditions expected. Winds gusting as high as 
  85 MPH.

* WHERE...Bordeaux along Interstate 25 between Chugwater and 
  Wheatland.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Widespread blowing snow could significantly reduce
  visibility and create whiteout conditions. The cold wind 
  chills as low as 15 below zero could cause frostbite on exposed 
  skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ110-120000-
/O.CON.KCYS.BZ.W.0004.000000T0000Z-211212T0000Z/
North Snowy Range Foothills-
Including the cities of Arlington and Elk Mountain
1047 AM MST Sat Dec 11 2021

...BLIZZARD WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Blizzard conditions likely. Winds gusting as high as 85 
  MPH.

* WHERE...Interstate 80 near Arlington and Elk Mountain.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Widespread blowing snow will cause significant 
  reduction in visibility and whiteout conditions. The cold wind 
  chills as low as 20 below zero could cause frostbite on 
  exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ109-120000-
/O.CON.KCYS.BZ.W.0004.000000T0000Z-211212T0000Z/
Central Carbon County-
Including the city of Rawlins
1047 AM MST Sat Dec 11 2021

...BLIZZARD WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Blizzard conditions possible. Winds gusting as high as 
  60 mph.

* WHERE...Central Carbon County especially east of Rawlins.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Widespread blowing snow will cause significant 
  reduction in visibility and whiteout conditions. The cold wind 
  chills as low as 20 below zero could cause frostbite on 
  exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
296 
WWUS45 KCYS 112102
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
202 PM MST Sat Dec 11 2021

WYZ110-120100-
/O.EXT.KCYS.BZ.W.0004.000000T0000Z-211212T1200Z/
North Snowy Range Foothills-
Including the cities of Arlington and Elk Mountain
202 PM MST Sat Dec 11 2021

...BLIZZARD WARNING NOW IN EFFECT UNTIL 5 AM MST SUNDAY...

* WHAT...Blizzard conditions likely. Winds gusting as high as 85
  MPH.

* WHERE...Interstate 80 near Arlington and Elk Mountain.

* WHEN...Until 5 AM MST Sunday.

* IMPACTS...Widespread blowing snow will cause significant 
  reduction in visibility and whiteout conditions. The cold wind 
  chills as low as 20 below zero could cause frostbite on 
  exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ109-120100-
/O.EXT.KCYS.BZ.W.0004.000000T0000Z-211212T1200Z/
Central Carbon County-
Including the city of Rawlins
202 PM MST Sat Dec 11 2021

...BLIZZARD WARNING NOW IN EFFECT UNTIL 5 AM MST SUNDAY...

* WHAT...Blizzard conditions possible. Winds gusting as high as 
  60 mph.

* WHERE...Central Carbon County especially east of Rawlins.

* WHEN...Until 5 AM MST Sunday.

* IMPACTS...Widespread blowing snow will cause significant 
  reduction in visibility and whiteout conditions. The cold wind 
  chills as low as 20 below zero could cause frostbite on 
  exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ106-120000-
/O.CON.KCYS.BZ.W.0004.000000T0000Z-211212T0000Z/
Central Laramie Range and Southwest Platte County-
Including the city of Bordeaux
202 PM MST Sat Dec 11 2021

...BLIZZARD WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Blizzard conditions expected. Winds gusting as high as 80
  MPH.

* WHERE...Bordeaux along Interstate 25 between Chugwater and 
  Wheatland.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Widespread blowing snow could significantly reduce 
  visibility and create whiteout conditions. The cold wind 
  chills as low as 15 below zero could cause frostbite on 
  exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
094 
WWUS45 KCYS 120013
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
513 PM MST Sat Dec 11 2021

WYZ106-120115-
/O.EXP.KCYS.BZ.W.0004.000000T0000Z-211212T0000Z/
Central Laramie Range and Southwest Platte County-
Including the city of Bordeaux
513 PM MST Sat Dec 11 2021

...BLIZZARD WARNING HAS EXPIRED...

Local areas of blowing snow reducing visibilities down to one 
mile will be possible overnight through early Sunday morning along
I-25 and area roadways from Chugwater to Wheatland. Ground 
blizzard condition chances have decreased and thus the warning 
has been allowed to expire. High winds will continue overnight 
while the snow begins to crust over and become slightly less 
blowable to cause local impacts. 

$$

WYZ110-121200-
/O.CON.KCYS.BZ.W.0004.000000T0000Z-211212T1200Z/
North Snowy Range Foothills-
Including the cities of Arlington and Elk Mountain
513 PM MST Sat Dec 11 2021

...BLIZZARD WARNING REMAINS IN EFFECT UNTIL 5 AM MST SUNDAY...

* WHAT...Blizzard conditions. Winds gusting as high as 80 mph.

* WHERE...Interstate 80 near Arlington and Elk Mountain.

* WHEN...Until 5 AM MST Sunday.

* IMPACTS...Widespread blowing snow will cause significant 
  reduction in visibility and whiteout conditions. The cold wind 
  chills as low as 20 below zero could cause frostbite on 
  exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ109-121200-
/O.CON.KCYS.BZ.W.0004.000000T0000Z-211212T1200Z/
Central Carbon County-
Including the city of Rawlins
513 PM MST Sat Dec 11 2021

...BLIZZARD WARNING REMAINS IN EFFECT UNTIL 5 AM MST SUNDAY...

* WHAT...Blizzard conditions. Winds gusting as high as 65 mph.

* WHERE...Central Carbon County especially east of Rawlins.

* WHEN...Until 5 AM MST Sunday.

* IMPACTS...Widespread blowing snow will cause significant 
  reduction in visibility and whiteout conditions. The cold wind 
  chills as low as 20 below zero could cause frostbite on 
  exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Travel should be restricted to emergencies only. If you must
travel, have a winter survival kit with you. If you get stranded,
stay with your vehicle. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$
818 
WWUS45 KCYS 120927
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
227 AM MST Sun Dec 12 2021

WYZ109-110-121030-
/O.CAN.KCYS.BZ.W.0004.000000T0000Z-211212T1200Z/
Central Carbon County-North Snowy Range Foothills-
Including the cities of Rawlins, Arlington, and Elk Mountain
227 AM MST Sun Dec 12 2021

...BLIZZARD WARNING IS CANCELLED...

Areas of blowing snow will remain possible today. However,
blizzard conditions are no longer expected. 

$$

CLH

The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 10, 2:55 PM MSTHigh Wind WarningCYSAlbany, Carbon, Converse, Laramie, Platte50 hr

Nearby

Blizzard Warnings in Wyoming, 2021Every blizzard warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.